The formation of thallous chloride on thallium amalgam has been examined at constant potential. At low overpotentials the deposit grows with (100) planes parallel to the substrate while at high overpotentials the orientation changes to (1 10). At the low overpotentials a monomolecular layer is first produced, the slow stage of crystal growth being the formation of the lattice at the edges of two-dimensional growth centres. A multimolecular layer is then deposited by the twodimensional growth of centres on top of the monomolecular layer. At higher overpotentials the successive deposition of two monomolecular layers is observed, followed by the deposition of a multimolecular layer. At low overpotentials the slow stage, in the mechanism of lattice formation, is the successive incorporation of two thallium ions; at high overpotentials the rate of crystal growth at the periphery of the two-dimensional centres becomes diffusion controlled.

Mercury cadmium telluride (HgCdTe) processing must be performed at a low temperature in order to reduce Hg depletion. To meet demand, low-temperature plasma enhanced atomic layer deposition (PE-ALD) is an emerging deposition technology for highly conformal thin films. We comparatively studied the effectiveness of low-temperature PE-ALD by measuring the ALD film roughness, thickness, and dielectric values. Conformal deposition was investigated through scanning electron microscopy images of the Al 2 O 3 film deposited onto high aspect ratio features dry-etched into HgCdTe. PE-ALD demonstrated conformal coatings of trenches, pillars and holes in advanced HgCdTe infrared sensor architectures.

One-dimensional nanostructures such as silicon nanowires (SiNW) are attractive candidates for low power density electronic and optoelectronic devices including sensors. A new simple method for SiNW bulk synthesis[1, 2] is demonstrated in this work, which is inexpensive and uses low toxicity materials, thereby offering a safe, energy efficient and green approach. The method uses low flammability liquid phenylsilanes, offering a safer avenue for SiNW growth compared with using silane gas. A novel, duo-chamber glass vessel is used to create a low-pressure environment where SiNWs are grown through vapor-liquid-solid mechanism using gold nanoparticles as a catalyst. The catalyst decomposes silicon precursor vapors of diphenylsilane and triphenylsilane and precipitates single crystal SiNWs, which appear to grow parallel to the substrate surface. This opens up possibilities for synthesizing nano-junctions amongst wires which is important for the grid architecture of nanoelectronics proposed by Likharev[3]. Even bulk synthesis of SiNW is feasible using sacrificial substrates such as CaCO3 that can be dissolved post-synthesis. Furthermore, by dissolving appropriate dopants in liquid diphenylsilane, a controlled doping of the nanowires is realized without the use of toxic gases and expensive mass flow controllers. Upon boron doping, we observe a characteristic red shift in photoluminescence spectra. In summary, an inexpensive and versatile method for SiNW is presented that makes these exotic materials available to any lab at low cost.

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